If a point has polar coordinates r=-5 and θ =4π/3, what are the Cartesian coordinates of the point?
◯ (-5/2,5√3/2)
◯ (-5/2,-5√3/2)
◯ (-5√3/2,-5/2)
◯ (5√3/2,5/2)
◯ (5/2,5√3/2)
◯ (5/2,-5√3/2)